Eric Swalwell, a California Democrat, has suggested forcing owners of so-called “assault weapons” to give them up voluntarily or do so by force, and face jail time if it comes to that, NBC News is reporting.

In an almost-shockingly bold op-ed piece in Thursday’s USA Today, Swalwell uttered the words that very few supporters of gun control have been willing to say: he suggests confiscation of assault weapons. Specifically, he says that the government should at least compensate owners of such weapons, offering them $1,000 per weapon in a federal buyback program. That would cost the government about $15 billion to buy back an estimated 15 million such weapons in the U.S.

“Ban assault weapons and buy them back. It might cost $15 billion, but we can afford it. Consider it an investment in our most important right, the right to live.”

By way of example only, GunBroker.com currently has five assault weapons listed for sale, each costing over $1,200, and one coming in at $3,000.

Swalwell’s idea is almost unprecedented in the gun-control debate in the U.S. Even the most ardent supporters of gun rights, notes NBC News‘ Benjy Sarlin, shy away from calling for confiscation of weapons, favoring instead more modest proposals such as universal background checks and banning (but not outright confiscating) assault weapons.

In his piece, Swalwell suggests taking things a step further. Reinstating the assault weapons ban, which was in place between 1994-2004 but repealed under the George W. Bush administration, would be a step in the right direction. But it would still leave millions of such weapons on the streets.

“Instead, we should ban possession of military-style semiautomatic assault weapons, we should buy back such weapons from all who choose to abide by the law, and we should criminally prosecute any who choose to defy it by keeping their weapons. The ban would not apply to law enforcement agencies or shooting clubs.”

Salwell suggests Australia’s gun buyback program as an example of a successful gun-confiscation measure. In 1996, the Land Down Under issued a mandatory gun buyback after a gunman killed 35 people. Over 640,000 guns in the country were bought back, some of them with force. There hasn’t been a mass shooting in Australia since.

However, Sarlin, writing for NBC News in April, said that Australia’s program is a non-starter in the U.S. That’s because gun-control advocates don’t want to be seen as supporting door-to-door confiscation. Even Kris Brown, co-president of the Brady Campaign, which advocates against gun violence, isn’t on board with confiscating existing firearms.

“I think it’s pretty clear from the program we do support that it’s about keeping guns out of dangerous hands and not about confiscating guns.”

Further, says Sarlin, even gun-control advocates note that a gun-confiscation program would be “difficult to enforce,” especially considering limited federal resources.